The present invention relates to damper structures, and more particularly to a ventilated damper assembly for use in metallurgical operations.
In large gas-conducting conduit systems such as those used in conjunction with metallurgical operations, it frequently is necessary to provide a damper to control gas flow through the conduit.
In the past, damper assemblies have proven to be complicated and expensive in order to effect positive tight sealing, and in many cases, have not proven entirely effective. Included among the past damper arrangements have been damper plates which slide into and out of a conduit in the manner of a guillotine. A problem with these damper plates is that they move in guiding rails and must fit therein with sufficient clearance to compensate for expansion and contraction of the damper plate to avoid binding. However, these damper plates must also be sized to obtain a gas tight seal when in the closed position. A further problem with sliding damper plates is that they tend to abrate the sealing surfaces of the guiding rails because they slide against them in moving between opened and closed positions. Yet a further drawback with sliding damper plates of the above-described type is that their use is substantially restricted to rectangular shaped conduits.